package day12;

public class Package_Demo {
    public static void main(String[] args) {
        int a=100;
        Integer a1=a;
        String s = String.valueOf(a1);
        String s1 = String.valueOf(a);
        System.out.println(s+" "+s1);
        double b=2.22;
        Double b1=b;
        String s2 = String.valueOf(b);
        String s3 = String.valueOf(b1);
        System.out.println(s2+" "+s3);

        String str1="123";
        Integer str2 = Integer.valueOf(str1);

        System.out.println(str2);
        int str3 = Integer.parseInt(str1);
        System.out.println(str3);
        System.out.println("---------");

        String x="121";
        String y="121.121";
        int x1 = Integer.parseInt(x);
        double y1 = Double.parseDouble(y);
        System.out.println(x1+" "+y1);

      /*  int x2 = Integer.parseInt(y);*/ double y2 = Double.parseDouble(x);
        System.out.println("交换之后"/*+x2*/+" "+y2);
    }
}
